Apparatus for use in forming concrete slabs



w. R. KELL 3,109,217

APPARATUS FOR USE IN FORMING CONCRETE SLABS Nov. 5, 1963 2 Sheets-Sheet 1 Filed Feb. 27, 1961 INVENTOR. Wa/aa 1?. /(e// BY 4 ,MM

A77'ORNE 5,

Nov. 5, 1963 Filed Feb. 27, 1961 w. R. KELL 3,109,217

APPARATUS FOR USE IN FORMING CONCRETE SLABS 2 Sheets-Sheet 2 INVENTOR.

Wa/do R Ke United States Patent 3,109,217 APPTUS Fon USE is got; CONCRETE SLAB Waldo R. Kell, Kansas City, Mo., assignor to The Lawrence Paper Company, Lawrence, Karts, a corporation of Kansas Filed Feb. 27, 1961, Ser. No. 91,778 1 Claim. (Cl. 25131.5)

This invention relates to concrete construction equipment and more particularly to apparatus of primarily cardboard construction for use in forming concrete floor slabs.

It is the most important object of this invention to provide a cardboard or fiber concrete form, which form is held in position with respect to a supporting surface upon-which the concrete is to be poured, there being a frame initially secured to said supporting surface and then secured to the form assembly whereby to retain the form in a fixed position relative to said supporting surface before, during and after the pouring of the concrete.

Yet another important aim of this invention is to provide a frame for retaining the form in position, which frame is comprised of a plurality of strips of triangular cross-sectional configuration, a portion of the form cover being secured to said strips whereby to lock the cover to the frame and thus to the supporting surface.

it is a yet further aim to provide a form assembly which includes a core and a cover, the cover being secured to a polygonal frame whereby the form assembly is held against horizontal movement and the core is protected against water damage by virtue of the seal created between the cover, the frame and the surface upon which the apparatus is supported.

It is a yet further aim of the present invention to provide apparatus which is economical in cost and which may be re-used to form several concrete slabs, thus resulting in a saving of time and money for the contractor using such apparatus.

Another object of this invention is to provide apparatus which includes a frame and a form, the frame having the normally uppermost surface thereof inclined relative to the surface upon which the frame is supported and the form having a cover, a portion of which overlies and is secured to said uppermost surface whereby the outer configuration of the cover is imparted to beams fonning a part of the concrete slab which results from use of the subject apparatus.

Other objects of the present invention include details of construction which will become apparent from the following specification and accompanying drawing wherein:

FIGURE 1 is a perspective view illustrating various components of the subject apparatus and the steps involved in positioning the same for use;

FIG. 2 is a top plan view of the apparatus, parts being broken away and in section to reveal details of construction;

FIG. 3 is an enlarged, fragmentary, sectional view of one corner of the cover and frame;

FIG. 4 is a sectional view taken on line 44 of FIG. 3; I

FIG. 5 is a perspective view of a slab formed by use of the subjected apparatus and illustrating the steps in removing components of the apparatus from the finished slab;

FIG. 6 is a sectional view of the apparatus showing the same positioned within a concrete slab; and

FIG. 7 is a view similar to FIG. 4 but showing a modified form of the apparatus.

The apparatus forming the subject of this invention is broadly designated by the numeral 10 and includes as its primary components a core unit 12, a cover 14 for said core 12 and a frame assembly 16 to which a portion of said cover 14 is secured.

Apparatus It) is normally used in conjunction with a supporting surface such as a plywood deck 18, chosen for purposes of illustration, or the same may be used in connection with spaced supporting members such as sofiltts which are likewise used as form supporting members in the construction of concrete slabs.

it will be appreciated that deck 18 is suitably supported by upright columns (not shown) and is positioned between main supporting beams which are poured or placed in position at the desired location prior to the erection of deck 18. Deck 18 and apparatus 10 are, in the particular form chosen for illustration, used to form concrete floor slabs of a wafile type, such slabs being so named because of the appearance of one surface thereof, such surface being illustrated, for instance, in FIG. 5 of the drawing.

In the erection of apparatus 10 for subsequent use in forming concrete slabs, the frame assembly 16 is first positioned on deck 18 and secured thereto by suitable fastening means such as nails 20. Frame assembly 16 consists of a plurality of strips 22, each of said strips 22 being of triangular cross-sectional configuration whereby to present a first leg 24, a second leg 26 and an inclined, normally uppermost surface 28. As best seen in FIG. 4, first leg 24 is disposed in perpendicular relationship to deck 18, second leg 26 is in overlying engagement with the upper surface of said deck 18 and surface 28 of strips 22 is inclined relative to deck 18, this angle of inclusion being substantially 45 degrees. The adjacent and abutting ends of strips 22 are suitably mitered as shown in FIG. 3 whereby the same can be brought into abutting relationship to define a closed frame. In the form chosen for illustration, frame assembly 16 is comprised of strips 2-2 substantially equal in. length whereby to define a square frame, but it will be appreciated that any number of strips such as 22 of varying lengths may be used whereby to define a frame assembly having any desired configuration.

To aid inpositioning frame assembly 16 at the necessary and desired location upon deck 18, a template 30.

may be used, said template having outer dimensions equal to those desired for the inner edges of the frame and being positionable through the use of a handle 32. Thus template 30 is positioned at the intersection of previously formed chalk lines such as 34- and 36 illustrated in FIG. 1 and the strips 22 may then be positioned about the peripheral edge of the template 30 by bringing first legs 24 of strips 22 into engagement with the peripheral edge portion of template 30. After strips 22 have been secured to deck 18 .by nails 20 template 30 may be lifted from within frame assembly 16 and re-used to position the next frame assembly such as 16.

Subsequent to the positioning and securement of frame assembly 16 as above described, core unit 12 is unfolded from the flat condition in which it is shipped and stored and formed into the shape illustrated in the drawings.

Core unit 12 includes a plurality of first partition members 38 and a plurality of second partition members 40, all of said partition members being disposed vertically with respect to deck 18 and the first and second partition members being disposed in perpendicular relationship to one another, as best seen in FIG. 2 of the drawing. It will be noted that first and second partition members '38 and 40 cooperate to define chambers such as 42, said chambers 42 being substantially equal in size. It has been found, however, that additional rigidity and supporting ability is imparted to core unit 12 if the outermost chambers 44 thereof are smaller than the normally inner chambers 42. Thus the ends of first partition members 38 3 extending beyond the outermost second partition members 40 are shortened, and likewise the ends of second partition members 4% extending beyond outermost first partition members 38 are likewise shortened whereby to present a plurality of smaller chambers 44 aboutthe edges of core unit 12.

Core unit 12 rests upon the upper surface of deck 18 p and is supported thereby within the confines of frame assembly 16. The outermost ends of first partition members 38 and second partition members 46, at their lowermost areas, abut leg 24 of strips 22 forming frame assembly 16 and this abutment serves to retain core unit 12 in its desired position and to hold the same against its tendency to assume a flattened condition.

Once the core unit 12 has been disposed in the position above described, cover 14 is moved into position by sliding the same over core unit 12 in the manner best illustrated in FIG. 1.

Cover 14 is substantially box-like in configuration, having a plurality of vertical walls 46 and a flap member 48 hinge'dly secured to the normally uppermost edge of corresponding vertical walls 46. Each of walls 46 has a line of bend 50 spaced from the normally lowermost edge 52 of wall 46, edge 52 and line of band being in substantially parallel relationship. Line of bend Sit and lowermost edge 52 define therebetween a marginal edge portion 54 for each vertical wall 46. As cover 14 is moved into position with respect to core unit 12, marginal edge portions 5 4 are swung outwardly whereby, when the cover 14 is fully in place, portions 5'4 overlie inclined uppermost surfaces 28 of strips 22, as is best seen in FIG. 4 of the drawing. Thus the major portion of cover 14, which consists of walls 46 and flaps 48, encloses core unit 12 and marginal edge portions 54 are secured to surface 28 of corresponding strips 22 by suitable fastening means such as staples 56 whereby to retain the cover unit 14 in a fixed position relative to frame assembly 16 and thus to deck 18. Flaps 48 are then moved to their closed position overlying the upper edges of partition members 38 and 40 and the joints therebetween are taped shut as by tape 58. The securement of edge portions 54 to strips 22 by staples 56 insures a tight seal between the cover 14 and frame assembly 16 and this seal serves to prevent the admission of water to the interior of cover 14 and thus to core unit 12.

To funther insure that cover 14 and core unit 12 retain their configuration against both the elements and the concrete which is subsequently poured over apparatus dil partition members 38 and 40 are formed from an asphalt impregnated cardboard material, both the flutes 6b of said partitions and the liners 62 being so impregnated. Likewise, cover 14 is formed from an asphalt impregnated cardboard material, the inner liner 64 of the cardboard from which cover 14 is formed being asphalt impregnated and the flute portions 66 of the cardboard of cover 14 being likewise so impregnated. For purposes which will be hereinafter made clear the outer surface of the normally outer liner 68 of the cardboard forming cover 14 is coated with a suitable plastic material such as polyethylene.

After apparatus has been fully positioned in the manner above described, concrete 70 is poured thereover, it being usually contemplated that there will be a plurality of form members such as herein described positioned upon a deck 18 whereby to provide the desired number of beams such as 72 which form a part of the concrete floor slab 74. As is apparent, once concrete 70 has been poured over apparatus 10 the same is allowed to set and apparatus 10 may then be removed from its position within concrete beam 72 and slab 74.

The above mentioned removal is accomplished by first removing the supports for deck 18 and pulling the same downwardly from beneath concrete 7i Strips 22 of frame assembly 16, being secured to deck 18, will be pulled from their position of use as the deck '18 is re- 7 moved from its supporting position. After the removal of deck 18 and strips 22 core unit 12 can be slid downwardly and removed from its position within cover 14, as illustrated in FIG. 5 of the drawing. Cover 14 may then be removed by pulling the same downwardly, as is also shown in FIG. 5, and it will be appreciated that the polyethylene coating upon the outer surfaces of cover 14 prevents the same from sticking to the concrete and aids materially in the removal thereof. Once the core unit and cover have been removed as above described, they may be flattened and stored or may be moved to the next succeeding deck to again be re-used in the manner above described. Likewise, strips 22 may, after their removal from deck 18, be re-used to form subsequent frame assemblies.

As is shown in FIG. 5 particularly, the use of strips 22, in addition to the benefits above described, results in the beams 72 having angularly inclined surfaces 76, which surfaces are desirable Y in exposed beam construction. Thus the angle of inclination of surface 28 of strips 22 imparts an equal angular trim to the exposed corners of beams 72, such angular trim being desirable in many types of concrete construction.

As above indicated and as illustrated in the drawing, it is usually contemplated that the lowermost edge 52 of walls 46 of cover 14 will be in substantial alignment with the point of juncture between surface 28 of strips 22 and the upper surface of deck 18. In such a form of the invention the normally lowermost face 78 of beams 72 is formed by the upper surface of deck 18. If it is desired to have the same finish on face 78 as is-prov-ided for the remaining lower portion of slab 74 and the side portions of beam '72, the cover may be formed and positionedin the manner illustrated in FIG. 7 of the drawing. In this modified form the cover 114 has the normally lowermost portion 116 thereof secured to the deck 118, said portion 116 being defined by a first line of bend 120, there being a second, parallel line of bend 122 spaced from line of bend 12% whereby to define av strip engaging pontion 124, which portion 124 is secured to the inclined surface of the corresponding frame strips. As is apparent, the use of a modified form of the cover as above described and as illustrated in FIG. 7 results in the lowermost face 7 S of beams 72 having the same finish as the remaining lower portion of the concrete slab 74 and a the side portions of beams 72.

The use of apparatus as above described results in substantial economies in the forming of concrete slabs inasmuch as apparatus 10 is formed primarily of cardboard material, the cardboard material being treated and constructed in such a manner that it is impervious not only to the elements but to damage by workmen and others in the process of erecting and utilizing apparatus 10 whereby such apparatus may be re-used a number of times.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

Apparatus for use in forming concrete slabs upon a supporting surface comprising a polygonal frame secured to said supporting surface, the frame being formed from a plurality of strips having a triangular cross-sectional configuration whereby to present an inclined, normally uppermost surface and an opposed vertical inside surface; and a form retained in a fixed postion upon said supporting surface by said frame, said form including a core having vertical edges disposed within the confines of the frame and normally in engagement with the inside vertical surfaces of the frame and resting upon said supporting surface, said inside vertical surfaces being relatively narrow with respect to the height of the vertical edges of the core, and a cover enclosing said core, said cover being polygonal whereby to present a plurality of normally vertical walls normally in engagement with said vertical edges of the core, each of said Walls having a line of bend therein parallel to the lowermost edge thereof and spaced from said lowermost edge, said line of bend and said edge cooperating to define a marginal edge portion for each Wall of said polygonal cover, said marginal edge portions each outward-1y overlying the inclined, normally uppermost surface of a corresponding strip and being secured thereto in abutting relation.

References Cited in the file of this patent UNITED STATES PATENTS Knutson May 26, 1931 Goldsmith Feb. 23, 1932 MacDonald Dec. 27, 1932 Caril-li Sept. 21, 1937 Bowes Dec. 7, 1937 Miller Feb. 18, 1958 Raney Apr. 14, 1959 

